A. The first mentor in my career was a man called Johnny Johnson, who was the team leader in a computer group. He demanded the highest standards from everybody that worked for him. He would not tolerate any low-quality work. He was completely demanding of people’s commitment. But he gave absolute loyalty in return. It was a very good set of disciplines that have stood me well for the rest of my career.

Q. Which businessman or woman do you most admire?

A. In the public market, for me it is still Lord Browne [of Madingley] who, I think, has created a remarkable business. He’s done it courageously, but he’s consistently delivered value. He’s highly regarded by many people, but I think he is worthy of the admiration. I think in the private equity market it’s Henry Kravis who, together with George Roberts, established the blueprint for an industry, and did it by developing professionalism to the highest standard.

Q. Do you read books on management? If so, which one has influenced you the most?

A. I’ve read many. There are two which probably stood the test of time. One is Sun Tzu: The Art of War, which is still very relevant in terms of strategy and tactics, whether in military sense or business sense. The other is Jack Welch And The GE Way by Robert Slater. Clearly it’s a little less fashionable than it used to be, but I think the principles are good basic rules for business.

Q. What is the most important business event, good or bad, to occur in your working life?

A. Undoubtedly the most important event in my life was teaming up with Nigel Rudd at Williams. It was the beginning of the most exciting, the most rewarding, the most fulfilling period of my business life. The wonderful thing about Williams was that the chemistry was excellent, there was absolute mutual respect and common ambition.

Q. Which is more important: what you know, or who you know, and why?

A. I think without doubt your value is based on your knowledge, your skill, your ability to make a contribution. That’s the core. It’s also fair to say that you need someone who will trust you in order to give you the chance to demonstrate that what you know is valuable to who you know. Therefore, at the end, it is a combination of the two, based on what you know, that makes it work.

Q. What does leadership mean to you?

A. I think leadership is obtaining the commitment and the enthusiasm from other people. And I think to gain that you have to give clarity of vision. Your communication has to be clear and crisp and your execution has to be efficient. But most of all it has to have strong integrity that everybody sees and believes in. You’ve got to be absolutely sure about the vision and what you want to achieve — and to have other people accept that vision and then buy into it, which they will only do if you communicate it clearly.

Q. If you could change one thing about the business, financial and commercial environment, what would it be?

A. This is relevant to Centrica. I think it would be to ensure that there is truly a level playing field in the European regulated industry area — in the utilities. The more liberal approach in the UK has opened up all markets to all competition without barriers and has enabled the continental players to establish a bridgehead here while we struggled because of regulation to get a foothold there. The sooner that is repositioned to be a level playing field the better and fairer things will be.

Q. Does money motivate you?

A. The thing I would say at this stage of life is, the more I have managed to accumulate, the less it has been the key motivational drive. There’s no doubt that it is a component of motivation, and at the start of life it is a very meaningful one. If you haven’t got a privileged background and it is up to you how you create a quality of life for you and your family, then money’s an important part of that.

Q. What gadget/piece of technology can you not do without?

A. I think if you have multiple roles and a mobile life you need points of absolute certainty. One is the mobile telephone and the other is the BlackBerry. When I first got involved with KKR about three years ago, the BlackBerry was a standard tool they had. I was fascinated by e-mail on the move, which meant that you were never away.

Q. How do you relax?

A. Golf, opera, ballet, some cinema. But most valuable is time spent with friends and family.

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